If this is a front loader you are probably closing the door after you use it, this prevents the machine from drying out properly between uses and encourages mold growth, i.e stench. Run the machine with a strong bleach solution and then run again with just water to make sure all the bleach has rinsed away. Leave the door slightly open after each use so that the machine drys out properly. This is a common problem and most people don't realize that they should leave the door slightly open after using the machine so that it can dry out.
Dark Overlord
August 2008
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